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1.
Through in-depth interviews, an inventory has been made of the experiences of 18 liver patients who have been considered for or undergone a liver transplant. Interviews were also held with the patients' relatives. Chronic patients especially seem to regard a transplant as their last chance, and all their hopes become based on it. The strict selection procedure is distressing, and being turned down causes negative feelings. As far as the operation itself is concerned, patients are inclined to create high success rates for themselves in relation to their survival chances and the expectations of quality of life. For some patients a transplant means a marked improvement in the various aspects of their functioning. Others are not so fortunate, but do not give up hope of improvement. From the relatives of the patients who had died post-operatively, no negative feelings were encountered over the 'failure' of the technology'. 相似文献
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Ross BD; Jacobson S; Villamil F; Korula J; Kreis R; Ernst T; Shonk T; Moats RA 《Radiology》1994,193(2):457
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Video-rate nonlinear microscopy of neuronal membrane dynamics with genetically encoded probes 总被引:4,自引:0,他引:4
Biological membranes decorated with suitable contrast agents give rise to nonlinear optical signals such as two-photon fluorescence and harmonic up-conversion when illuminated with ultra-short, high-intensity pulses of infrared laser light. Microscopic images based on these nonlinear contrasts were acquired at video or higher frame rates by scanning a focused illuminating spot rapidly across neural tissues. The scan engine relied on an acousto-optic deflector (AOD) to produce a fast horizontal raster and on corrective prisms to offset the AOD-induced dispersion of the ultra-short excitation light pulses in space and time. Two membrane-bound derivatives of the green fluorescent protein (GFP) were tested as nonlinear contrast agents. Synapto-pHluorin, a pH-sensitive GFP variant fused to a synaptic vesicle membrane protein, provided a time-resolved fluorescent read-out of neurotransmitter release at genetically specified synaptic terminals in the intact brain. Arrays of dually lipidated GFP molecules at the plasma membrane generated intense two-photon fluorescence but no detectable second-harmonic power. Comparison with second-harmonic generation by membranes stained with a synthetic styryl dye suggested that the genetically encoded chromophore arrangement lacked the orientational anisotropy and/or dipole density required for efficient coherent scattering of the incident optical field. 相似文献
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Hilhorst MI van Ewijk E Veenhoven RH Roorda RJ 《Nederlands tijdschrift voor geneeskunde》1999,143(49):2449-2452
Two boys aged 13 and 7 years, displayed chronic coughing, dyspnoea on exertion, anorexia, weight loss, and fatigue. At first a diagnosis of asthma was made. However, a correct interpretation of anamnestic and clinical features, laboratory findings and radiographic results led to the diagnosis of 'pigeon breeder's disease' in both cases. Both patients recovered after drug treatment and avoidance of re-exposure to pigeon antigen. 相似文献
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This review discusses published evidence on the use of metered dose inhaler (MDI)/spacer combinations and nebulizers for delivering β2 adrenoeeptor agonists (β2 agonists) in stable and acute severe childhood asthma. Although nebulizers have been the mainstay of inhalation therapy in childhood asthma for many years, these devices are cumbersome, bulky, time-consuming, and expensive to use. As a result, over the past decade the emphasis of inhalation therapy in children has shifted from nebulizers to metered-dose inhalers (MDI) in combination with spacer devices. MDI/spacer combinations have been shown to be a practical and effective way of delivering medications for inhalation in children with asthma, irrespective of their age. Lung deposition increases with age, being low in young children. This underscores the need for administering relatively high nominal dosages of medication when using an MDI/spacer in young children; the most practical approach is to use the same dose, irrespective of the child’s age or weight. In children with both stable chronic asthma and acute severe asthma, numerous studies have shown that β2 agonists can be delivered by MDI/spacer at least as effectively and safely as by nebulizer. Although nebulizers may still play a role in status asthmaticus (because they allow combined administration of β2 agonists, anticho-linergic agents, and oxygen in a single procedure), the vast majority of children of all ages with acute severe asthma can be managed effectively and safely by β2 agonists delivered via MDI/spacer. This cost-effective and practical approach should, therefore, be preferred. 相似文献
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BD White A Kong E Khoo AM Southcott 《Journal of Medical Imaging and Radiation Oncology》2005,49(4):319-321
Tracheobronchopathia osteochondroplastica (TO) is a rare benign disease characterized by the presence of osseous and cartilaginous submucosal nodules projecting into the tracheobronchial tree. Most cases are asymptomatic and discovered incidentally at post‐mortem. We identified a case of TO on thoracic spiral CT and confirmed the diagnosis on bronchoscopy. This article reviews the imaging characteristics of TO, and shows the 3‐D virtual bronchoscopic and multiplanar reconstruction appearances of TO. 相似文献
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WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
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